Fluid-pressure-actuated clamp particularly for rock-drill mountings



1. H. VEASEY. FLUID PRESSURE' ACTUATED CLAMP PARTICULRLY FR ROCK DRILL MOUNTINGS.

- APPLICATION FILED NOV. 25,19I9- v 1,404,179. l Paten an. 17, 1922.

l EETS-SIIEET I. 6

1. H. vEAsEY. num PRESSURE Acumu CLAMPy PARlcuL/RRLY roR RocR DRILL Moumms.

l APPLICATION FILED NOV. 25| 1919. 1,404,179, Patented Jan. 17, 1922.

NVENTR J'OH/V HERERT LCE/955) s). @mq/1MM UNITED STATES PATENT OFFICE.

FLUID-PRE'SSURE-ACTUATED CLAMP PARTICULARLY FOR ROCK-DRILL MOUNTINGS.

moeite.

Application filed November 26, 1919.

To all'whom t may concern.'

' Be it known that JOHN HERBERT VEAsEY, a British subject, residing at 14; Ansteys Buildings, Kerk Street, Johannesburg, Transvaal Province of the Union of South Africa, has invented certain new and ,useful Improvements in Fluid-Pressure-Actuated Clamps Particularly for Rock-Drill l.\Iountings, of which the following is a specification.

The present invention relates to clamping devices actuated by fluid pressure and par* ticularly to such devices embodied in mountings for rock drills. In the specification of my Transvaal Patent No. 269/15, I have described a rock drill arm which is secured to its column by a hydraulic clamp, and also a. hydraulic clamp for securing the drillingT machine to the arm. In these constructions a cylinder and a plunger were employed; and when using low pressure fluid these parts become somewhat bulky.

It is `the object of the present invention to provide an improved construction which is lighter, less bulky and'cheaper than those employing a cylinder and piston and in which the pressure area can be varied without undue expense.

According to the present invention the clamping and unclamping movement is attained by means of a flexible diaphragm exposed to the fluid pressure. A small movement of the diaphragm is suflicient to apply or relieve the tightening pressure; if further adjusting movement is required. it may be attained by manually actuated mechanism such, for instance, as a cam, bolt and nut, or the like.

'Ihe diaphragm may be formed of any suitable flexible material such as rubber fabric, leather andthe like in which case a pressure plate may be interposed between the diaphragm and the part onto which it presses in order to protect it from damage. A corrugated or other flexible metal plate may also be used and may itself form the pressure plate or it may be provided with a separate pressure plate.

In the accompanying drawings,

Fig. I shows one form of the improved clamp secured to an arm.

Fig. II is a partial plan of Fig. I.

Fig. III shows a modified construction of the clamp, employed for securing an arm to a column.

Fig. IV is a cross sectional view of the Specification of Letters Patent.

Patented J an. 17, 1922.

Serial No. 840,823.

clamping plate of Fig. III, drawn to an enlarged scale.

Referring to Figs. I and II, 1 indicates the foot of a rock drilling machine, and 2 an arm to which the rock drilling machine is to be clamped.

The' clamp consists of the two jaw elements 3 and 4. The parts of the clamp are connected by bolts 5 which also serve to grip the foot 1 and so secure it to the jaw element 3.

The pressure element comprises a metal frame comprising a back plate 6 and side walls. It is conveniently formed from sheet metal by first cutting it to shape and then bending up the lside walls from the back G so as to form first an upstanding wall 7 all around, then an inturned flange 8, and then an upturned flange 9; said parts 7, 8 and 9 being `welded together at the corners 10. A flexible diaphragm 11 is pressed into the recess 12 formed between the back plate 6, the wall 7, and the flange 8, so making a joint with the frame all around its edge. A loose pressure plate 13 is .dropped into the recess bounded by the upstanding flanges 9 and is retained in place by suitable stops indicated by 14. The pressure plate 13 makes contact with the jaw member 4..

At the back of theV pressure member is a cross bar 15. to which the bolts 5 are pivotally secured; the head ends of these bolts being passed into place through recesses 16 formed in the jaw member 3. 17 is a connection by which fluid under suitable pressure is conveyed between the plate 6 and the flexible diaphragm 11.

In operation the clamp members are arranged in position as shown and upon pressure fluid being admitted through the connection 17 the diaphragm is forced outwards, taking with it the pressure plate 13v and the jaw 1, and so forcing the clamp members together.

In the modified construction shown in Figs. III and IV the positioning of the clamp members is effected by other than the fluid pressure means and said means is employed simply to produce the final tightening pressure. Since in this case the movement of the diaphragm can be kept within a very small limit, practically the whole area of the diaphragm can be kept always in contact with the part against which it presses, the pressure plate is dis- Y this case the column on which it grips.

l can be brought In these drawings 18 indicates a column to which the arm 2 is clamped. On the arm is formed one element 19 ofthe clamp. From said partV 19 extend bolts 2O carrying a cross shaft 21. a cam 22 provided with a handle 28. Said cam 22 bears against a bearing plate 24 on the back of the pressure member 25 so-that by rotating the cam the pressure member into contact with the column 18.v

The pressure member itself consists of a single plate 25 curved to fit the column 18. The flexible diaphragm 11 is held inplace b y turning over the edges 26 of the plate 25. A water connection 27 is fixed at 28 (Fig. I) to deliver pressure water behind the diaphragm; the clamping operation being effectedin this case as in the first example.

In order to hold the flexible diaphragm clear of the column when the diaphragm is slacked there may be fitted one or more thin flatsprings 29 whichare shaped to conform to the surface of the diaphragm and are clipped at their edges around the edge of the plate 25.

It will be seen in both of the above examples that owing tothe rectangular shape of the pressure member and the narrow dead edge of the saine, a considerable effective pressure area can be obtained with a pres- Vsure device of moderateV size. If it is desired fined edgeand arranged for movement to A phragm.

able for rock drill mountings, comprising a frame, a flexible diaphragm inserted into the frame and having a narrow edge clamped therein and means to apply fluidV pressure between the back of thev frame and the dia- 3. A fluid pressure actuated clamp suitable lfor rock drill mountings, comprising a Said shaft 21 rotatably supportsv frame, a flexible diaphragm mounted in the frame and having a narrow edge ysecured therein, a movable pressure plate in front of the diaphragm and means to apply pressure fluid to the other side of theV diaphragm.

l. A fluid actuated clamp suitable for rock drill mountings, comprisingV relatively movable clamp elements, a flexible diaphragm associated with one of said clamp elements and arranged for movement. tov apol i clam in@ )ressure said dia )hraofm having a narrow edge only confined, means t0 a] 1 ly.pressiire fluid to a face of said dia-y phragm to effect such Vclamping movement and additional mechanism for ,producing relativefmovement of the clamp members. Y

5.V The combination with a rock drill arm,

of a drill carrying clamp comprising twoV clamp elements connected against separating movement, a flexible diaphragm associated with one of said clamp elements, and means to apply fluid pressure behind said diaphragm, the diaphragm moving under the influence of the fluid pressure Vto cause the clamp element to grip the arm. f

6. The combination with a rock drill arm, of a clamp device constructed simultaneously to grip the arm and to secure a rock drill to the clamp, a flexible diaphragm forl actuating the clamp and means to apply fluid pres sure to the diaphragm to move the same for that purpose.

7. A rock drill 'armclamp, comprising two j clamp elements adapted to grip a drillY arm between them. and one of, said elements af-Y fording a seating for a drill foot, connecting means extending for the other clamp element and constructed to engage a drill yli'oot positioned on said seating, a flexible diaphragm embodied in the clamp structure and adapted to move to tension said connecting means and means to apply fluid pressure to the diaphragm so to move it.

8. A rock drill arm `clamp comprising two jaw elements adapted to grip the armV be tween them, a cross member` bolts extending from said cross member and shaped at their free ends to engage a drill foot with theopposite jaw element and a pressure element between Athe crossmember and the adjacent j aw element comprising a flexible diaphragm and means to supply fluid pressurethereto.

In testimony thereof I affix my signature. 

